Week 8- gram negative

Question 1

Bordetella pertussis

Answer 1

causes whooping cough—interferes with action of ciliated epithelial cells in trachea; has 3 phases: cold like symptoms, coughing deeply, disease subsides but secondary infection can occur

Question 2

E. coli

Answer 2

commonly causes gastroenteritis (most common disease associated with this bacteria)—watery diarrhea, cramps, nausea and vomiting. It is most common cause of non-nosocomial urinary tract infections (UTI’s), can
lead to acute pyelonephritis. O157:H7 strain can cause bloody diarrhea, fatal hemorrhagic colitis or severe kidney disorder—leading to renal failure

Question 3

Haemophilus influenzae b

Answer 3

can cause meningitis (stiff neck, severe headache) as well as pneumonia, inflammation of subcutaneous tissue, infantile arthritis and life threatening epiglottitis that blocks airway

Question 4

Neisseria meningitides

Answer 4

spread via respiratory droplets–causes meningococcal meningitis because bacteria goes to CSF (abrupt sore
throat, fever, stiff neck, vomiting and convulsions)-can progress rapidly resulting in death

Question 5

Neisseria gonorrhoeae

Answer 5

causes sexually transmitted disease called gonorrhea—affects mucous membranes of genital, urinary and digestive tracts. Symptomatic in men (urethral inflammation, painful urination and purulent penile discharge) but can be asymptomatic in women. Infects cervix in women and can lead to Pelvic Inflammatory disease.

Question 6

Pseudomonas aeruginosa

Answer 6

this is strictly an OPPORTUNISTIC infection that can colonize almost every organ or system (bacteremia, endocarditis, urinary and central nervous system)—infects burn victims (under wound bandages) and the lungs of cystic fibrosis patients. Has a distinct green pigment.

Question 7

Salmonella enterica

Answer 7

causes non-bloody diarrhea, nausea and vomiting as well as fever, myalgia, headache and abdominal cramps– usually due to consumption of contaminated poultry or eggs

Question 8

Salmonella typhi

Answer 8

enters GI tract and then blood stream causing high fever (it gradually increases), abdominal pain with diarrhea or constipation, loss of appetite, can cause a rash, headache, muscle pains, fatigue and can cause peritonitis if colon is perforated—transmitted via ingestion of food or water contaminated with bacteria from
carriers (many are asymptomatic

Question 9

Shigella dysenteriae

Answer 9

starts in small intestine and travels to large intestine; causes severe dysentery due to strong enterotoxin—
characterized by abdominal cramps, fever, bloody diarrhea with pus or mucus. Can have 20% mortality rate. Primarily transmitted by poor hygiene or contaminated sewage—secondarily by contaminated food

Question 10

Yersinia enterocolitica

Answer 10

causes painful inflammation of the intestinal tract. Abdominal pain, fever and diarrhea that can last for weeks to months (if infects lymph nodes can mimic appendicitis)—most commonly acquired via consumption of milk,
water or food (especially raw or undercooked pork) contaminated with animal feces

Question 11

Yersinia pestis

Answer 11

Causes pneumonic plague (when it travels from blood to lungs). Causes fever malaise and pulmonary distress. It is 100% fatal without treatment. It also causes bubonic plague (high fever and swollen painful lymph
nodes—if enters blood (septicemic) will eventually causes death of tissue because it causes hemorrhaging of blood
vessels—“black plague”). It can be carried by rats or mice

Question 12

Borrelia burgdorferi

Answer 12

transmitted by ticks–causes lyme disease (bulls-eye rash then malaise, headache, dizziness, severe fatigue , fever, chills and muscle joint pain. Later– neurological symptoms and cardiac dysfunction and final stage is severe arthritis

Question 13

Campylobacter jejuni

Answer 13

probably the MOST COMMON cause of bacterial gastroenteritis in US—animals (zoonotic) are reservoirs. Humans get infected by eating contaminated food (uncooked or undercooked), water or milk infected with animal feces. Produces fever, malaise, abdominal pain, nausea, vomiting and frequent bloody diarrhea (10 or more BM’s
per day)—body gets rid of it so only lasts about one week—usually does not require treatment

Question 14

Chlamydia trachomatis

Answer 14

causes lymphogranulonum veneruem (most common sexually transmitted disease in US)—usually starts with genital lesion that is not painful. Followed by swollen lymph nodes (buboes)—which may rupture and produce draining sores. Fever, chills, anorexia and muscle pain also occur. Third stage is genital sores. Infected women can be asymptomatic but infected men can have urethritis. Women who get re-infected can get PID. Also can cause eye infection and blindness

Question 15

Helicobacter pylori

Answer 15

This bacteria can neutralize stomach acid–causes gastritis and most peptic ulcers (erosions of mucous membrane of stomach)—stomach pain (including burning pain), loss of appetite, bloating

Question 16

Rickettsia rickettsia

Answer 16

causes Rocky Mountain Spotted Fever (transmitted via ticks)— about a week after exposure patients experience fever, headache, chills, muscle pain, nausea and vomiting. Develop spotted, non-itchy rash—even on
palms and soles of feet

Question 17

Treponema palladum

Answer 17

causes syphilis (4 stages of the sexually transmitted disease). Starts with chancre at site of infection—most on external genitalia but can be on mouth, anus, fingers, lips or nipples. It travels to blood to cause secondary: sore
throat, fever, headache, malaise, myalgia and widespread painless rash. Next is latent phase and can eventually become tertiary : can affect any tissue including bones, nervous tissue or skin (form gummas)

Question 18

Vibrio cholera

Answer 18

causes abrupt, watery diarrhea (characteristic rice-water stool); contracted by drinking contaminated water –
infects intestinal tract and can lead to SEVERE fluid and electrolyte loss and death.

Question 19

Both Rickettsias are unique (not like typical gram negative bacteria)—what makes each Genus unique?

Answer 19

extremely small
almost appear wall-less
in ticks
obligate intracellular parasites

Question 20

Both Chlamydias are unique (not like typical gram negative bacteria)—what makes each Genus unique?

Answer 20

no cell walls
obligate intracellular pathogens
do not make atp
unique developmental cycle involving 2 from-ebs and rbs

Question 21

What does the shape of a Spirochete allow it to do?

Answer 21

Moves in a corkscrew fashion through its
environment
* Enables pathogenic spirochetes to burrow through hosts’ tissues

Question 22

Which microbes that we studied (from matching) are spirochetes?

Answer 22

Borrelia
Treponema pallidum

Question 23

How does the Lipid A endotoxin get released from a Gram Negative bacteria and what does the endotoxin trigger in humans?

Answer 23

broken down/digested or, reporduction releases lipid a

fever, vasodilation, inflammation, shock, and
disseminated intravascular coagulation (DIC)

Question 24

Briefly describe each of the 6 common pathogenicity factors of enteric bacteria (not including lipid A)

Answer 24

1-Fimbrae and adhesins (proteins): allow bacteria to attach tightly to human cells

2-Exotoxins

3-Plasmid (has virulence genes)

*4-iron binding compounds (allow iron to be used by the bacteria)

5-Hemolysins

6-Type III Secretion system (a needle like structure that injects proteins into the host cell)